EP1118842B1 - Air meter - Google Patents
Air meter Download PDFInfo
- Publication number
- EP1118842B1 EP1118842B1 EP01100126A EP01100126A EP1118842B1 EP 1118842 B1 EP1118842 B1 EP 1118842B1 EP 01100126 A EP01100126 A EP 01100126A EP 01100126 A EP01100126 A EP 01100126A EP 1118842 B1 EP1118842 B1 EP 1118842B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- circuit
- reference voltage
- current
- temperature
- flow rate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 230000003321 amplification Effects 0.000 claims description 4
- 238000003199 nucleic acid amplification method Methods 0.000 claims description 4
- 238000006243 chemical reaction Methods 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 3
- 239000006185 dispersion Substances 0.000 description 3
- 238000001514 detection method Methods 0.000 description 2
- 230000020169 heat generation Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/68—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using thermal effects
- G01F1/696—Circuits therefor, e.g. constant-current flow meters
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/68—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using thermal effects
- G01F1/696—Circuits therefor, e.g. constant-current flow meters
- G01F1/6965—Circuits therefor, e.g. constant-current flow meters comprising means to store calibration data for flow signal calculation or correction
Definitions
- This invention relates to an air meter, particularly to an air meter for measuring air mass flow suitable for the use of engine control for an automobile.
- a ratio-metric output type air meter having an output characteristic adjusting circuit and a ratio-metric converting circuit, as shown in JP10148556 .
- a ratio-metric output type air meter is known having an output characteristic adjusting circuit and a voltage controlled oscillator circuit.
- An object of this invention is to provide an air meter in which in case where a plurality of internal reference power supply circuits are needed, it is possible to improve the accuracy of the internal reference voltage with fewer IC terminals.
- an air meter contains a characteristic adjusting circuit for adjusting the characteristic of a flow rate signal detected by flow rate detecting means, by using a first internal reference voltage, and outputting the flow rate characteristic signal, a conversion circuit converting the flow rate characteristic signal which this characteristic adjusting circuit outputs, to a ratio-metric output or a frequency output on the basis of a second internal reference voltage, and a reference power supply circuit for said first and second internal reference voltages, said internal reference power supply circuit comprising: a temperature current generating circuit for generating a current proportional to a temperature; a current mirror circuit for duplicating the current of this temperature current generating circuit, in that a first and a second current are created; a first reference voltage generating circuit through which said first current flows and which is arranged to generate said first reference voltage; and a second reference voltage generating circuit through which said second current flows and which is arranged to generate said second reference voltage.
- said temperature current generating circuit uses as a resistor a thick-film resistor, and said first and second reference voltage generating circuits use a monolithic resistor and a thick-film resistor, respectively.
- a flow rate detecting circuit 3 comprises a heat generating resistor 1 positioned in an air flowing path, and a constant temperature controlling circuit 2.
- the heat generating resistor 1 receives a current from the constant temperature controlling circuit 2, and is heat-controlled by self heat generation.
- the constant temperature controlling circuit 2 detects an air flow rate from the magnitude of heat current by controlling the heat current to maintain the resistance of the heat generating resistor 1 to a predetermined value, and generates a flow rate detection signal V2.
- An output characteristic adjusting circuit 4 adjusts the characteristic of the flow rate detection signal V2 by adjusting a zero point and an amplification factor on the basis of Equation (1), thereby to generate a flow rate characteristic signal V4 by adjusting the output signal of the air meter to a predetermined characteristic.
- an internal reference voltage ES generated by a band gap reference power supply circuit 6 is used.
- V ⁇ 4 K ⁇ 1 ⁇ V ⁇ 2 - K ⁇ 2 ⁇ ES
- K1 is a constant for adjusting the amplification factor
- K2 is a constant for adjusting the zero point.
- a multiplication circuit 5 constituting a ratio-metric conversion circuit compares the internal reference voltage VINT generated by the band gap reference power supply circuit 6 with an external reference voltage VREF supplied from an engine control unit connected to the air meter, and converts the flow rate characteristic signal V4 created by the output characteristic adjusting circuit 4 to a ratio-metric characteristic on the basis of Equation (2), thereby to output an output signal VOUT from the air meter.
- VOUT K ⁇ 3 ⁇ V ⁇ 4 ⁇ VREF / VINT
- K3 is a constant.
- the engine control unit not shown in the drawings includes an AD converter for converting the signal of the air meter to a digital signal to control the engine using the signal of the air meter.
- Equation (2) can be expressed as following Equation (3) using Equation (1).
- VOUT K ⁇ 1 ⁇ V ⁇ 2 - K ⁇ 2 ⁇ FS ⁇ K ⁇ 3 ⁇ VREF / VINT
- a semiconductor integrated circuit is effectively arranged by using a band gap reference power supply circuit 6 as means for generating the internal reference voltages ES and VINT.
- any dispersion of the band gap reference power supply circuit 6 depends upon the dispersion of the transistors and resistors constituting it, the use of external resistors such as thick-film resistors formed on a circuit substrate on which an IC is mounted is suitable rather than the use of monolithic resistors integrated within an IC, because the dispersion of resistances and voltages is small.
- the former produces the problem that the number of terminals of the IC for connecting the transistors within the IC to the external resistors is increased.
- a temperature current IT of which current value is proportional to the absolute temperature is generated by a temperature current generating circuit 21, and two internal reference voltages ES and VINT are generated by supplying temperature currents duplicated by a current duplicating circuit 22 to a reference voltage generating circuit 23 and a reference voltage generating circuit 24.
- the reference voltage generating circuits 23 and 24 each comprises respective diodes or transistors and a respective resistor as shown in the drawing.
- the temperature characteristic of the forward voltage-drop voltage VF of the diode connection is negative with respect to temperature change, if it is added to the voltage drop of the resistor through which the current proportional to a temperature is flowed, it is possible to counterbalance any temperature change.
- Fig. 2 is a circuit diagram showing the arrangement of the air flow rate meter according to the second embodiment of this invention.
- the same reference numerals as those in Fig. 1 indicate the same parts or components.
- a flow rate detecting circuit 3 an output characteristic adjusting circuit 4 and a multiplier circuit 5 are the same as the corresponding ones in Fig. 1.
- a band gap reference circuit 6A comprises a temperature current generating circuit 21A, a current duplicating circuit 22, a reference voltage generating circuit 23A and a reference voltage generating circuit 24A.
- the temperature current generating circuit 21A is made up transistors 25 and 26.
- the emitter of the transistor 25 is connected to a terminal 50, and the emitters of the transistors 26 is connected to a terminal 37.
- temperature currents IT of which values are proportional to the absolute temperature are supplied.
- the terminal 37 is connected to an external resistor 27 such as a thick-filmresistor, and the terminal 50 is connected to the external ground potential.
- the current duplicating circuit 22 is the same as the corresponding one of the Fig. 1.
- the reference voltage generating circuit 23A comprises series-connected transistors 28 and 29, and resistors 30 and 31.
- the resistors 30 and 31 are connected to a terminal 39 for connecting thereto an external resistor.
- the resistor 30 is a monolithic resistor and the resistor 31 is a thick-film resistor which is the external resistor.
- the reference voltage generating circuit 23A has the output which is connected to an external connection terminal 40 through a voltage follower 36 to supply the reference voltage ES to the output characteristic adjusting circuit 4.
- the reference voltage generating circuit 24A comprises series-connected transistors 32 and 33 and resistors 34 and 35 of which interconnections act as a terminal 38 to which an external resistor is connected.
- the resistor 34 is a monolithic resistor and the resistor 35 is a thick-film resistor which is the external resistor.
- the band gap reference circuit 6A has the almost components housed within an IC and has four terminals 37, 38, 39 and 50 to which external resistors such as thick-film resistors are connected. Therefore, it is possible to use as the resistors as used in the reference voltage generating circuits 23A and 24A the combination of the external thick-film and inside IC monolithic resistors, and to correct the linearity of the temperature characteristic of the reference voltage.
- the resistors as used in the reference voltage generating circuits 23A and 24A the combination of the external thick-film and inside IC monolithic resistors, and to correct the linearity of the temperature characteristic of the reference voltage.
- the zero point of the air meter and the temperature of the span as well as the temperature characteristic linearity of the zero point and the temperature characteristic linearity of the span, respectively, can be adjusted to their respective optimum values.
- Fig. 3 is a circuit diagram showing the arrangement of the air flow rate meter according to the third embodiment of this invention.
- the reference numerals as used which are the same as those in Fig. 1 identify the same parts or components.
- a flow rate detecting circuit 3 and an output characteristic adjusting circuit 4 are the same as the corresponding ones of Fig. 1.
- the multiplier circuit 5 as used in Fig. 1 is replaced with a VCO (voltage controlled oscillator) circuit 7.
- the VCO circuit 7 converts the output voltage signal V4 of the output characteristic adjusting circuit 4 to a frequency signal, and generates the output signal VOUT of the frequency output type air flow rate meter.
- the band gap reference power supply circuit 6 generates an internal reference voltage ES for the output characteristic adjusting circuit 4 and an internal reference voltage VINT for the VCO circuit 7.
- the band gap reference power supply circuit 6 comprises a temperature current generating circuit 21, a current duplicating circuit 22 and reference voltage generating circuits 23 and 24.
- the temperature current generating circuit 21 generates an temperature current IT of which value is proportional to the absolute temperature, and generates two internal reference voltages ES and VINT by supplying temperature currents duplicated by using the current duplicating circuit 22 to the reference voltage generating circuit 23 and the reference voltage generating circuit 24, respectively.
- the reference voltage generating circuits 23 and 24 each is made up two diodes or transistors and a resistor as shown in the drawing. Since the temperature characteristic of the forward voltage-drop voltage of the diode connection is negative with respect to any temperature change, if the voltage drop due to the resistor through which the current proportional to the temperature is flowed is added to it, it is possible to cancel any temperature change and to generate a reference voltage of which value does not change depending upon the temperature change, using a selected resistor.
Description
- This invention relates to an air meter, particularly to an air meter for measuring air mass flow suitable for the use of engine control for an automobile.
- As the prior art air meter, a ratio-metric output type air meter is known having an output characteristic adjusting circuit and a ratio-metric converting circuit, as shown in
JP10148556 - However, in both of the ratio-metric output type air meter and the frequency output type air meter, two circuits of the respective air meters have independent internal reference power supply circuits, and to assure their accuracy it is necessary that a resistor is connected to the external of a monolithic IC, and therefore, it is necessary that the IC has connection terminals of the number proportional to the number of the internal reference power supply circuit outputs.
- An object of this invention is to provide an air meter in which in case where a plurality of internal reference power supply circuits are needed, it is possible to improve the accuracy of the internal reference voltage with fewer IC terminals.
- The above-mentioned and other objects of this invention can be attained by an air meter according to
claim 1. It contains a characteristic adjusting circuit for adjusting the characteristic of a flow rate signal detected by flow rate detecting means, by using a first internal reference voltage, and outputting the flow rate characteristic signal, a conversion circuit converting the flow rate characteristic signal which this characteristic adjusting circuit outputs, to a ratio-metric output or a frequency output on the basis of a second internal reference voltage, and a reference power supply circuit for said first and second internal reference voltages, said internal reference power supply circuit comprising: a temperature current generating circuit for generating a current proportional to a temperature; a current mirror circuit for duplicating the current of this temperature current generating circuit, in that a first and a second current are created; a first reference voltage generating circuit through which said first current flows and which is arranged to generate said first reference voltage; and a second reference voltage generating circuit through which said second current flows and which is arranged to generate said second reference voltage. - With this arrangement, it is possible to improve the precision of the internal reference voltages with few terminal of IC.
- In accord with another aspect of this invention, preferably said temperature current generating circuit uses as a resistor a thick-film resistor, and said first and second reference voltage generating circuits use a monolithic resistor and a thick-film resistor, respectively.
- With this arrangement, it is possible to correct the linearity of the temperature characteristics of the reference voltages.
-
- Fig. 1 is a circuit diagram of an air meter according to a first embodiment of this invention;
- Fig. 2 is a circuit diagramof an air meter according to a second embodiment of this invention; and
- Fig. 3 is a circuit diagramof an airmeter according to a third embodiment of this invention.
- Hereinafter, the arrangement of an air meter according to a first embodiment of this invention will be explained using Fig. 1. The explanation is given by exemplifying a ratio-metric output type air meter.
- A flow
rate detecting circuit 3 comprises aheat generating resistor 1 positioned in an air flowing path, and a constant temperature controllingcircuit 2. The heat generatingresistor 1 receives a current from the constant temperature controllingcircuit 2, and is heat-controlled by self heat generation. The constant temperature controllingcircuit 2 detects an air flow rate from the magnitude of heat current by controlling the heat current to maintain the resistance of theheat generating resistor 1 to a predetermined value, and generates a flow rate detection signal V2. - An output characteristic adjusting
circuit 4 adjusts the characteristic of the flow rate detection signal V2 by adjusting a zero point and an amplification factor on the basis of Equation (1), thereby to generate a flow rate characteristic signal V4 by adjusting the output signal of the air meter to a predetermined characteristic. In order to adjust the zero point of the output characteristic adjustingcircuit 4, an internal reference voltage ES generated by a band gap referencepower supply circuit 6 is used.
In this Equation (1), K1 is a constant for adjusting the amplification factor and K2 is a constant for adjusting the zero point. - A
multiplication circuit 5 constituting a ratio-metric conversion circuit compares the internal reference voltage VINT generated by the band gap referencepower supply circuit 6 with an external reference voltage VREF supplied from an engine control unit connected to the air meter, and converts the flow rate characteristic signal V4 created by the output characteristic adjustingcircuit 4 to a ratio-metric characteristic on the basis of Equation (2), thereby to output an output signal VOUT from the air meter.
In this Equation (2), K3 is a constant. - The engine control unit not shown in the drawings includes an AD converter for converting the signal of the air meter to a digital signal to control the engine using the signal of the air meter.
-
- From Equation (3), it is clear that since the internal reference power supply voltage ES causes the zero point to change and the internal reference voltage VINT causes the amplification factor to change, the internal reference power supply voltage ES and the internal reference voltage VINT are, if they are of independent characteristics, suitable to adjust the temperature characteristic of the air meter.
- Therefore, in this embodiment, a semiconductor integrated circuit is effectively arranged by using a band gap reference
power supply circuit 6 as means for generating the internal reference voltages ES and VINT. - Since any dispersion of the band gap reference
power supply circuit 6 depends upon the dispersion of the transistors and resistors constituting it, the use of external resistors such as thick-film resistors formed on a circuit substrate on which an IC is mounted is suitable rather than the use of monolithic resistors integrated within an IC, because the dispersion of resistances and voltages is small. However, the former produces the problem that the number of terminals of the IC for connecting the transistors within the IC to the external resistors is increased. - Accordingly, in the band gap reference
power supply circuit 6 according to this embodiment, a temperature current IT of which current value is proportional to the absolute temperature is generated by a temperaturecurrent generating circuit 21, and two internal reference voltages ES and VINT are generated by supplying temperature currents duplicated by a current duplicatingcircuit 22 to a referencevoltage generating circuit 23 and a referencevoltage generating circuit 24. - The reference
voltage generating circuits - As explained above, in this embodiment, it is possible to provide a plurality of high precision band gap reference power supply circuit of which characteristic can be set up independently, with few IC terminals, rather than two integrated reference power supply circuits.
- Next, the arrangement of an air flow rate meter according to the second embodiment of this invention will be explained. This embodiment will be explained using the example of a ratio-metric output type air flow rate meter.
- Fig. 2 is a circuit diagram showing the arrangement of the air flow rate meter according to the second embodiment of this invention. Incidentally, the same reference numerals as those in Fig. 1 indicate the same parts or components.
- In Fig. 2, a flow
rate detecting circuit 3, an output characteristic adjustingcircuit 4 and amultiplier circuit 5 are the same as the corresponding ones in Fig. 1. - A band
gap reference circuit 6A comprises a temperature current generatingcircuit 21A, a current duplicatingcircuit 22, a referencevoltage generating circuit 23A and a referencevoltage generating circuit 24A. - The temperature current generating
circuit 21A is made uptransistors transistor 25 is connected to aterminal 50, and the emitters of thetransistors 26 is connected to aterminal 37. To these terminals, temperature currents IT of which values are proportional to the absolute temperature are supplied. Theterminal 37 is connected to anexternal resistor 27 such as a thick-filmresistor, and theterminal 50 is connected to the external ground potential. The current duplicatingcircuit 22 is the same as the corresponding one of the Fig. 1. - The reference
voltage generating circuit 23A comprises series-connectedtransistors resistors resistors terminal 39 for connecting thereto an external resistor. Theresistor 30 is a monolithic resistor and theresistor 31 is a thick-film resistor which is the external resistor. The referencevoltage generating circuit 23A has the output which is connected to anexternal connection terminal 40 through avoltage follower 36 to supply the reference voltage ES to the outputcharacteristic adjusting circuit 4. Also, the referencevoltage generating circuit 24A comprises series-connectedtransistors resistors terminal 38 to which an external resistor is connected. Theresistor 34 is a monolithic resistor and theresistor 35 is a thick-film resistor which is the external resistor. - The band
gap reference circuit 6A has the almost components housed within an IC and has fourterminals voltage generating circuits monolithic resistor 30 and theexternal resistor 31 and the ratio of themonolithic resistor 34 and theexternal resistor 35, the zero point of the air meter and the temperature of the span as well as the temperature characteristic linearity of the zero point and the temperature characteristic linearity of the span, respectively, can be adjusted to their respective optimum values. - Also, in the example shown in Fig. 2, since the internal of the IC and the terminal for providing the connection to the external resistors are connected using few number of terminals such as four
terminals - Next, the arrangement of an air meter according to the third embodiment of this invention will be explained using Fig. 3. This embodiment will be explained using a frequency output type air flow rate meter.
- Fig. 3 is a circuit diagram showing the arrangement of the air flow rate meter according to the third embodiment of this invention. The reference numerals as used which are the same as those in Fig. 1 identify the same parts or components.
- In Fig. 3, a flow
rate detecting circuit 3 and an outputcharacteristic adjusting circuit 4 are the same as the corresponding ones of Fig. 1. Themultiplier circuit 5 as used in Fig. 1 is replaced with a VCO (voltage controlled oscillator)circuit 7. TheVCO circuit 7 converts the output voltage signal V4 of the outputcharacteristic adjusting circuit 4 to a frequency signal, and generates the output signal VOUT of the frequency output type air flow rate meter. - The band gap reference
power supply circuit 6 generates an internal reference voltage ES for the outputcharacteristic adjusting circuit 4 and an internal reference voltage VINT for theVCO circuit 7. Just like the case of Fig. 1, the band gap referencepower supply circuit 6 comprises a temperaturecurrent generating circuit 21, acurrent duplicating circuit 22 and referencevoltage generating circuits current generating circuit 21 generates an temperature current IT of which value is proportional to the absolute temperature, and generates two internal reference voltages ES and VINT by supplying temperature currents duplicated by using thecurrent duplicating circuit 22 to the referencevoltage generating circuit 23 and the referencevoltage generating circuit 24, respectively. - The reference
voltage generating circuits - As explained above, in this embodiment, it is possible to provide a plurality of high precision band gap reference power supply circuit of which characteristic can be set up independently, with few IC terminals, rather than two integrated reference power supply circuits.
- In accordance with this invention, in an air meter in which a plurality of internal reference power supply circuits are needed, it is possible to improve the degree of accuracy of an internal reference voltage with few IC terminals.
Claims (2)
- An air meter containing
a flow rate detecting means (3),
a characteristic adjusting circuit (4) arranged to adjust the characteristic of a flow rate signal V2 detected by said flow rate detecting means (3) by adjusting a zero point and an amplification factor using a first internal reference voltage ES, and outputting a flow rate characteristic signal V4,
a conversion circuit (5) arranged to convert the flow rate characteristic signal V4 to a ratiometric output or a frequency output VOUT of the air meter on the basis of a second internal reference voltage VINT, and
a reference power supply circuit (6) for providing said first and second internal reference voltages, characterized in that said internal reference power supply circuit (6) comprisesa temperature current generating circuit (21) for generating a current proportional to a temperature;a current mirror circuit (22) for duplicating the current of this temperature current generating circuit (21), in that a first and a second current are created;a first reference voltage generating circuit (23) through which said first current flows (22) and which is arranged to generate said first reference voltage ES; anda second reference voltage generating circuit (24) through which said second current flows and which is arranged to generate said second reference voltage VINT. - An air meter according to claim 1 wherein said temperature current generating circuit (21) uses a thick-film resistor (27) as a resistor include in said temperature current generating circuit (21), and said first and second reference voltage generating circuits (23, 24) include a monolithic resistor (30, 34) and a thick-film resistor (31, 35), respectively.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2000013370A JP3470073B2 (en) | 2000-01-21 | 2000-01-21 | Air flow meter |
JP2000013370 | 2000-01-21 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP1118842A1 EP1118842A1 (en) | 2001-07-25 |
EP1118842B1 true EP1118842B1 (en) | 2008-01-09 |
Family
ID=18540969
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP01100126A Expired - Lifetime EP1118842B1 (en) | 2000-01-21 | 2001-01-12 | Air meter |
Country Status (4)
Country | Link |
---|---|
US (2) | US6691568B2 (en) |
EP (1) | EP1118842B1 (en) |
JP (1) | JP3470073B2 (en) |
DE (1) | DE60132263T2 (en) |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3808038B2 (en) | 2003-01-14 | 2006-08-09 | 株式会社日立製作所 | Frequency output type hot-wire flow meter |
JP4515828B2 (en) * | 2004-06-02 | 2010-08-04 | 日立オートモティブシステムズ株式会社 | Heating resistor type air flow meter |
CN101419493B (en) * | 2007-10-25 | 2012-06-20 | 鸿富锦精密工业(深圳)有限公司 | Fan running monitoring device |
TWI417716B (en) * | 2007-11-02 | 2013-12-01 | Hon Hai Prec Ind Co Ltd | Fan operation detecting apparatus |
JP5304766B2 (en) * | 2010-10-26 | 2013-10-02 | 株式会社デンソー | Flow measuring device |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3060607B2 (en) | 1991-07-08 | 2000-07-10 | 株式会社デンソー | Hot wire flow meter |
JP2677923B2 (en) | 1991-12-06 | 1997-11-17 | 株式会社日立製作所 | Heating resistor type air flow meter |
JP2846613B2 (en) | 1996-02-28 | 1999-01-13 | 株式会社日立製作所 | Pulse output type hot wire air flow meter |
DE19629747C2 (en) * | 1996-07-23 | 1998-07-30 | Siemens Ag | Sensor device |
JP3300615B2 (en) * | 1996-11-19 | 2002-07-08 | 株式会社日立製作所 | Ratiometric output type heating resistor type air flow meter, heating resistor type air flow meter and engine control device |
DE19818315C1 (en) * | 1998-04-23 | 1999-09-16 | Siemens Ag | Radiometric sensor signal measuring device |
JP3385995B2 (en) * | 1999-03-01 | 2003-03-10 | 日本電気株式会社 | Overcurrent detection circuit and semiconductor integrated circuit incorporating the same |
US6361207B1 (en) * | 1999-06-04 | 2002-03-26 | Florida Rf Labs, Inc. | Temperature sensing termination |
-
2000
- 2000-01-21 JP JP2000013370A patent/JP3470073B2/en not_active Expired - Lifetime
-
2001
- 2001-01-12 DE DE60132263T patent/DE60132263T2/en not_active Expired - Lifetime
- 2001-01-12 EP EP01100126A patent/EP1118842B1/en not_active Expired - Lifetime
- 2001-01-22 US US09/765,400 patent/US6691568B2/en not_active Expired - Lifetime
-
2003
- 2003-06-03 US US10/452,143 patent/US7040159B2/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
DE60132263D1 (en) | 2008-02-21 |
EP1118842A1 (en) | 2001-07-25 |
US7040159B2 (en) | 2006-05-09 |
US20010009109A1 (en) | 2001-07-26 |
US20030192378A1 (en) | 2003-10-16 |
JP3470073B2 (en) | 2003-11-25 |
DE60132263T2 (en) | 2009-01-02 |
JP2001201382A (en) | 2001-07-27 |
US6691568B2 (en) | 2004-02-17 |
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